Project Summary/Abstract Osteoarthritis (OA) is the single most important cause of disability in mid and late life. About 27 million people in the United States suffer from this incurable process and 10 million have OA of the knee. Total knee arthroplasty (TKA) is a reliable treatment option for patients disabled by knee OA who have failed nonoperative treatment, with 58% of these surgeries being performed on patients 65 years or older. TKA surgeries were performed on more than 700,000 patients in the United States in 2012 and estimates expect this number to increase between 143% and 565% by 2050. Most patients experience pain relief within 6 to 12 weeks following TKA; however, 8 to 34% of patients experience chronic postsurgical pain, defined by the International Association for the Study of Pain as clinically important pain lasting more than 3 months after surgery, with limited improvement in functional outcomes often despite an uneventful surgical course and a satisfactory radiographic appearance. With one projected estimate of 3.48 million TKA surgeries per year in the USA by 2030, up to 500,000 patients annually could develop chronic pain following TKA. The objective of this project is to aid in the construction of a dataset that encompasses clinical, biological (omics), psychological, socioeconomical and imaging predictors for a diverse group of patients undergoing TKA. Rush University the largest provider of joint replacement surgery in Illinois, performing 2,100 TKA procedures in 2017. With our Institute for Translational Medicine (ITM) partners, the University of Chicago, and NorthShore University Health System our NCATS CTSA-funded program hub has extensive translational research expertise and serves a diverse patient population (>5 million) across many racial, ethnic and socioeconomic strata and collectively perform more than 4000 TKA procedures per year. The overall project goal of the proposed research study is to provide high fidelity clinical, biological and psychological data in conjunction with Clinical Coordination Center, the Data Integration and Resource Center, and the Omics Data Generation Center from patients undergoing TKA within our NCATS CTSA-funded program hub in line with NIH HEAL Initiative A2CPS. This information should enrich our understanding of how acute pain becomes chronic pain following surgery and enhance our ability to target effective preventive and treatment strategies for patients.